Apparatus for removing concrete articles from pallets and inverting said articles



R. S. BAKER Nov. 26, 1968 3,412,439 APPARATUS FOR REMOVING CONCRETEARTICLES FROM PALLETS AND lNVERTING SAID ARTICLES 11, 1964 6Sheets-Sheet 1 Original Filed Feb.

Nov. 26, 1968 R. s. BAKER 3,412,439

APPARATUS FOR REMOVING CONCRETE ARTICLES FROM PALLETS AND INVERTING SAIDARTICLES Original Filed Feb. 11, 1964 e Sheets-Sheet 2 Noy. 26, 1968 Rs. BAKER APPARATUS FOR REMO VING CONCRETE ARTICLES FRO PALLETS ANDINVERTING SAID ARTICLES 6 Sheets-Sheet .5

Original Filed Feb. 11, 1964 Nov. 26, 1968 R. s. BAKER 3,412,439

APPARATUS FOR REMOVING CONCRETE ARTICLES FROM PALLETS AND INVERTING SAIDARTICLES Original Filed Feb. 11, 1964 6 Sheets-Sheet 4 INVENTOR R0 BER-rS. BQKER m'kmcm w um ATTORNEYS Nov. 26, 1968 APPARATUS FOR REMOVINGCONCRETE ARTICLES FROM PALLETS AND INVERTING SAID ARTICLES OriginalFiled Feb. 11,

R S. BAKER 6 Sheets-Sheet 5 INVENTOR Rosam- S. BAKER ATTORNEYS Nov. 26,1968 R. s. BAKER 3,412,439

APPARATUS FOR REMOVING CONCRETE ARTICLES FROM PALLETS AND INVERTING SAIDARTICLES Original Filed Feb. 11, 1964 6 Sheets-Sheet 6 INVENTOR UnitedStates Patent.

3,412,439 APPARATUS FOR REMOVING CONCRETE ARTICLES FROM PALLETS AND INVERTING SAID ARTICLES Robert S. Baker, Tampa, Fla., assignor, by mesneassignments, to American Concrete Crosstie Corporation, Tampa, Fla., acorporation of Florida Original application Feb. 11, 1964, Ser. No.344,095, new Patent No. 3,305,907, dated Feb. 28, 1967. Divided and thisapplication Feb. 27, 1967, Ser. No. 618,745

3 Claims. (Cl. 251) ABSTRACT OF THE DISCLOSURE Apparatus to separatecured concrete members from pallets in which they are formed and curedand transport them to an accumulating area, wherein there is a carriagewith means to grip the members and there is means to hold the palletagainst movement during separation of the members, and the carriagetransports the members to one or more member-inverting cradles at theaccumulating area, the operating sequence being automatically andelectrically controlled.

Cross-reference to related application This application is a division ofco-pending application of Robert S. Baker, S.N. 344,095, filed Feb. 11,1964, now Patent No. 3,305,907, for machine for making prestressedconcrete members.

Background of the invention This invention relates to apparatus forremoving elongated concrete members from pallets in which they wereformed and cured, and particularly to such apparatus for use inconnection with machines for automatically making prestressed concretearticles.

In the above mentioned copending application, a machine is disclosed forautomatically making prestressed concrete members. The machine includesa platform along which pallets are advanced to stations for insertingstressing cables in the pallets and anchoring them therein, forstressing the cables, for pouring and molding the concrete member, fortransferring the molded member on its pallet to a transporting car forpassage through a curing tunnel, for loading the cured pallet back ontothe platform, for cutting the cables to free the cored member from thepallet, and for removing the cured member from the pallet. The operationis continuous and automatic.

The present invention is concerned only with the apparatus for removingthe cured concrete members from the pallets. Reference may be had to thecopending application for a complete disclosure of the machine forforming prestressed concrete members.

Summary of the invention The principal object of the present inventionis to provide means for removing cured concrete members from the palletson which they have been formed and cured, and to move them to a place ofstorage.

Another object of the invention is to provide means to lift a concretemember from the pallet, to transport the member from the path of palletmovement and to deposit the member in a position for removal from themachine.

A still further object of the invention is to provide concrete memberremoving apparatus of the type mentioned, which will invert the concretemember before depositing it for removal from the machine.

Yet another object is to provide concrete member removing apparatuswhich will be automatic in its opera- 3,412,439 Patented Nov. 26, 1968FIGURE 1 is a schematic plan view illustrating the lay-out of the entireprestressed concrete forming machine, and showing the position of theconcrete member removing apparatus with respect to the other parts ofthe machine;

FIGURE 2 shows in side elevation that portion of the machine whichincludes the concrete member removing apparatus;

FIGURES 3A and 3B together show a section through the machine at theconcrete member removing station, and are taken on the line 3-3 ofFIGURE 2;

FIGURE 4 is an enlarged section taken on the line 44 of FIGURE 3A,showing a portion of the mechanism for removing cured concrete membersfrom pallets in which they were formed;

FIGURE 5 is taken on the line 55 of FIGURE 3B and shows in end elevationthe mechanism for inverting cured concrete members and placing them onmeans to transport them from the machine;

FIGURE 6 is a view similar to FIGURE 5, showing the mechanism at the endof its concrete member inverting movement;

FIGURE 7 is a diagrammatic view of the circuits controlling the meansfor removing concrete members from pallets; and

FIGURE 8 is a diagrammatic view of the control circuits for the meansfor inverting the concrete members.

Description of the preferred embodiment Referring first to FIGURE 1,there is shown diagrammatically a plan of the entire apparatus withwhich the cable cutting mechanism of the present invention isparticularly designed for use. It consists of a rectangular orbit, orpath, 1 for a pallet transporting means. The transporting path includesa leg 2 along and above which a concrete member forming machine 3 islocated, and a parallel leg 4 substantially the whole length of which isenclosed by a curing tunnel 5. Connecting the ends of the legs 2 and 4,and completing the orbit are transfer pits 6 and 7 along whichtransporting cars 8 are shifted from the forming machine leg 2 of theorbit to the tunnel leg 4, and from the tunnel leg to the formingmachine leg.

The concrete member forming machine has a base 9 forming a bridge overthe leg 2 of the transport path, and a platform upon which variousstations, where the several required operations are performed, arelocated. These include (starting at the right end of the machine asshown in FIGURE 1) a pallet receiving station 10, the cable cuttingstation 11, a concrete member removal station 12, a pallet headercleaning station 13, a pallet cleaning station 14, an anchor insertingstation 15, a cable laying station 16, a cable stressing station 17, amolding and vibrating station 18, and a loaded pallet delivery station19.

The base 9 is formed of a pair of longitudinally extending, horizontallyspaced, vertical walls or legs 20, with a flat platform 21 resting uponthe tops of the legs. The legs, and the portion of the platform whichbridges the legs, forms a tunnel 22 through which the transporting kilncars 8 move. The platform is sufiiciently broad to project some distancebeyond the legs on either side of the tunnel. It is upon this platformthat the various opcrating stations, including the cable cuttingstation, are mounted.

Pallet tracks 23 are mounted on the platform 21, and extend the fulllength of the platform. The track, and the means for moving palletsalong the track, can be any appropriate type, and one specific track andpallet moving means is described in detail in the above mentionedcopending application.

The pallet 24, in which the concrete member is formed, and which forms atransporting receptacle for the member, is an elongated, trough-shapedmember having a flat bottom 25 and upwardly diverging side walls 26. Theends are formed by headers 27 and 28 which span the ends of thetrough-shaped member. Header 27 is rigidly fixed to the trough end,while header 28 is a movable one having no permanent connection to thetrough. The movable header is moved outwardly and held in its movedposition to stress the cables as described in detail in the copendingapplication. Each header has a plurality of cable openings 29, and acable anchor 30 is attached to the header in alignment with each of theopenings. When the cables are inserted in the openings they will be heldby the anchors during stressing and throughout the concrete memberforming and curing operations. Although the cable openings may have anydesired pattern, each header is shown as having four openings as seen inFIGURE 2.

After the concrete members are formed on the pallets, they are moved to,and through, the curing tunnel 5 and then transferred back to themachine leg of the apparatus. The pallets, with the cured concretemembers, are unloaded from the cars and onto the pallet track at thepallet receiving station, and then moved along the pallet track untilthey arrive at the cable cutting station 11. Here, the cables 31 are cutfree from the headers, so that the cable tension is released to thecured concrete member,

and the member is free to be removed from the pallet.

As soon as the cables have been cut, the pallet is advanced along thepallet track to the removal station 12 where the cured member, now freedfrom the pallet headers, is removed from the pallet. After being liftedfrom the pallet, the member is transported to an accumulating area 32.The member removal mechanism consists of elevators 33, mounted uponplatform 21, a transporting trolley 34 and a member turn-over assembly35 which enables the concrete members, that were cast upside down, to beplaced right side up in the accumulating area.

There are two elevators 33, one adjacent each rail of the pallet track23, with the two being between the pallet track rails. Each elevatorconsists of a pair of parallel, vertical guide tubes 36 mounted upon theplatform 21. A cylinder assembly 37 is mounted between the guide tubes,and a cylinder 38 and the guide tubes 36 are suitably joined byconnectors 39. Elevator platform 40 has a pair of depending rods 41slidable in the guide tubes 36. The piston rod 42 of the cylinderassembly is connected to the elevator platform, so that the platformwill rise and fall as the piston rod is extended and retracted.

The elevator platform carries a pair of pallet engaging arms 43pivotally connected at 44 to brackets 45 beneath the platform edges. Thearms have horizontal inoperative positions (see full line positions,FIG. 4) and vertical positions in which they grip the pallet sides tohold the pallet while a concrete member is being removed. Each arm has ahooklike end 46, remote from the pivots 44, to overlie the uppersurfaces of pallets at the removal station when the arms are raised toupright, operative position. The arms have projecting ends 47, whichform operating levers and are connected to control cylinder assemblies48. The cylinders 49 of these assemblies are connected to brackets 50 atthe opposite sides of the elevator platform 40 from the arms theycontrol. Piston rods 51 are pivotally connected at 52 to the operatinglevers 47. Operation of the cylinder assemblies will cause the arms tomove to and from operative, pallet-engaging position.

The transporting trolley 34 includes a carriage 53 movable along anoverhead rail 54, supported from the platform 21 by means of standards55. The rail can be an I-beam, and the carriage will have rollers 56movable along the bottom flange of the beam. The rollers are shownmounted in trucks 57 and the carriage body 58 is suspended by hangers 59from the trucks. The carriage body may take any desired form. It may bean elongated member, extending the major portion of the length of theconcrete member to be lifted. One or more vacuum heads 60 are mountedbeneath the body, for engagement with a concrete member to be moved froma pallet on the elevators 33. The vacuum head will be connected to asuitable vacuum source, not shown, by pipeline 61 controlled by valve62.

When a concrete member has been engaged by the vacuum heads, theelevators will be lowered, leaving the member suspended from the trolleycarriage. The trolley carriage may then move along the rail 54, carryingthe member from the pallet track to a position at one side of themachine adjacent the accumulation area 32. The trolley carriage ispowered by linear actuators to be described. At the end of the trolleypath, the concrete member is transferred from the carriage to theturn-over assembly 35.

The turn-over assembly consists of two mechanisms to turn the concretemember in two stages. The first stage mechanism 63 is in the form of acradle which receives the member from the trolley carriage and turns it90 while delivering it to the second stage mechanism 64. The secondstage is another cradle which rocks 90 and completes the inversion ofthe concrete member as it delivers it to the accumulating area 32. Acylinder assembly 65 at the edge of the accumulating area pushes themember from the second stage mechanism onto a storage space or onto asuitable conveyor 66 which may be used to carry the member from themachine.

The turn-over mechanism is mounted upon a frame 67 which includes seats68 at the sides. The first stage 63 has a shaft 69 journaled in bearings70 on the seats 68. A reversible power means 71 is mounted upon one ofthe seats and connected to the shaft. Near the ends of the shaft, thereare upstanding plates 72, each having a cradle recess 73 at its upperedge to receive a concrete member. The recess shape will be such that itwill closely embrace the sides of the member.

The second stage 64 also has a shaft 74, journaled in bearings 75 on theseats 68. A power means 76 is connected to the shaft. Shaft 74 hasupstanding plates near its ends, which have recesses 78, shaped toreceive the concrete member when turned on its side. The recesses of thesecond stage mechanisms are locted so as to lie in the arcuate path oftravel of concrete members in the first stage cradle, so that theconcrete members will come to rest in the recesses 78 of the secondstage mechanism as the first stage is rocked about its shaft axis.

Operation of the various mechanisms at the unloading station 12 isinitiated by two cams on a master cam shaft 79. A cam 80 controlsoperation of the concrete member engaging arm 47, and a cam 81 controlsoperation of the elevators. The remaining operations are controlled bymovement of the various parts of the mechanism, or the movement of theconcrete member from place to place.

Cam 80 has a recess 82 into which switch arm 83 will drop shortly afterthe cam cycle of rotation begins. When the switch arm drops in therecess, it closes a circuit from line 84 through line 85, switch 83,line 86, solenoid coil 87 of valves controlling cylinders 49, to causethe piston rods to extend to swing the arms 43 vertically, and line 88to return line 89. This will bring the arms 43 up along the sides of thepallet to insure its proper position and cause the hook ends of the armsto overlie the pallet side edges. Cam 81 will then operate to move itsswitch 90, by contact with cam rise 91, to close a circuit through thesolenoid 92 controlling upward movement of the elevator cylinder 38.This circuit is from line 84, through line 93, switch 90, line 94,solenoid 92 and line 95 to line 89. The elevators will rise, carryingthe pallet and concrete member upwardly until the concrete member ispressed tightly against the vacuum heads 60.

After a short pause, long enough for proper vacuum to build up, cam 81will release switch 90, and the switch will move to its oppositeposition making contact with line 96 which connects to solenoid coil 97controlling downward movement of cylinder 38. If there is no adhesionbetween the concrete member and the pallet, the pallet will fall freefrom the elevators. If the pallet sticks, arms 43 will pull it from theconcrete member as the elevators lower. After the elevators reach theirposition of rest and the cam cycle is almost completed, cam 80 willcause switch 83 to close with line 98 connected to solenoid coil 99 tolower the arms 43 to inoperative position.

When the concrete member reached its upper position in contact with thevacuum heads, it closed a switch 100 on the trolley carriage. When thecarriage is in position to receive a concrete member, it holds closed aswitch 101 on the trolley rail 94 (see FIG. 7). When the empty pallet isreplaced on the pallet track, it closes a switch 102 on the pallettrack. These three switches, 100, 101 and 102, are in a circuit with astarter relay coil 103 for the three-phase twelve coil, lineal actuatorswhich cause the movement of the trolley carriage along its rail. Startercoil 103 initiates movement from the member receiving position at theelevators to turn-over mechanism. The circuit for coil 103 includes aline 104 from line 84, switch 102, a switch 105 located at the turn-overmechanism first stage indicating that mechanism is in position toreceive the concrete member, line 106, coil 103, line 107 includingswitch 101 and switch 100, and line 108 to return line 89. Energizingcoil 103 closes relay contacts 109 establishing a holding circuit fromcoil 103 to line 108 through line 110 by-passing switches 101 and 100.The holding circuit includes a switch 111 mounted in the trolleycarriage to cut off the linear actuators at predetermined time. Starterrelay contacts 112, 113 and 114 are in the heavy duty lines 115, 116 and117 supplying the lineal actuators 118.

As the trolley carriage moves along its track, a cam 119, mounted on therail 54 at about its middle, strikes switch 111 and opens the holdingcircuit through relay coil 103. As switch 101 opened when the carriageleft the elevator station, coil 103 will be de-energized and the linealactuators will be cut off. The trolley carriage will coast into theturn-over station.

When the trolley carriage arrives at the turn-over station it closesswitch 120 on the rail 54. It also closes a switch 121 on the rail whichis in circuit with a coil 122 of valve 62 controlling the vacuum heads60. Closing switch 121 will reease the vacuum allowing the concretemember to drop from the carriage to rest in the cradle recesses 73 inthe first turn-over station plates. The recesses are in alignment withthe path of the concrete member travel on the trolley carriage, so thatthe member is carried endwise into the recesses by the carriage. Thus,it need drop but a very short distance when released by the vacuum headsto seat in the cradle.

As the concrete member drops from the carriage, switch 100 opens. Whenthe member seats in the cradle recesses 73, it closes switches 123 and124, both mounted on the cradle plates 72. As switches 120 and 102 arealready closed a circuit through line 104, switch 102, line 125, switch124, starter relay coil 126, line 127, switches 120 and 123 is closed.This closes relay contacts 128 in holding circuit 129 and closes relaycontacts 130, 131 and 132 in linear actuator feed lines 115, 116 and 117to energize the actuators in reverse direction and start the trolleycarriage back toward the elevator station. On the return trip, switch133 in holding circuit 129 strikes cam 119 to de-energize coil 126. Thiswill de-activate the linear actuators. When the carriage left theturn-over station, switch 120 opened, and when the trolley is correct-1y positioned at the elevator station, switch 101 is closed.

When the concrete member was placed in the cradle of the turn-over firststage, it closed a switch 134, located on the cradle plate 72 (see FIG.8). A switch 135, mounted on the shaft 74 of the second stage, strikesan abutment 136 on the support seat 68 when the second stage is inproper member-receiving position. A third switch 137, located on thetrolley rail 54 is closed by the carriage when at the elevator station.With these three switches closed, a hydraulic valve coil 138 isenergized to start power means 71 to rock the first stage cradle towardthe second stage. The coil circuit is from line 84 through line 139, thethree switches and line 140 to return line 89. As the first stage cradlerocks, a switch 105 on shaft 69 leaves at abutment 141 on seat 68 andopens so that the trolley carriage cannot move from the elevator stationuntil the first stage cradle returns to upright, concrete memberreceiving position.

When the first stage cradle reaches the second stage cradle, the load ofthe member is taken by the second stage. As the member moves into therecesses of the second stage cradle, switch 142, mounted on the cradleplate 79 adjacent the recess, will be closed. This closes a circuit fromwire 139 through wires 143, 144, switch 142, coil 145 and return line140. Coil 145 controls power means 76 to rock the second stage cradletoward the accumulating area 32. As the second stage cradle starts itsrocking movement, switch 134 on the first stage cradle plate opens asthe concrete member is moved out of the first stage cradle.

The rocking movement of the second stage cradle carries the concretemember to the accumulating area. As the member is placed on the area, itcloses switch 146 on the area in line 147 bridged between lines 143 and140. This line includes valve coil 148 controlling reverse movement ofthe power means 71 of the first stage. When the first stage returns toits original position, it again closes switch 105 in the trolleycarriage control circuit. A second switch 149 on the accumulating areais also closed when the member is placed there. This switch is incircuit through line 150 with a solenoid coil 151 controlling the valveof cylinder assembly 65, and when switch 149 is closed the cylinder willoperate to push the concrete member from the second stage cradle ontothe conveyor 66. As the member moves off the switch 149, the switchopens and the cylinder automatically returns to its inoperativeposition. As the member leaves the second stage cradle, switch 142opens, breaking the circuit to the second stage power means. When themember is pushed onto the conveyor, a switch 152 is closed which is inline 153 to valve coil 154 controlling reverse movement of the secondstage cradle. The return of the second stage to its original positioncloses switch 135 on the second stage shaft, to set up the circuits torepeat the cycle.

When the empty pallet was returned by the elevators 33 to the pallettrack, it was in position to be moved by the next step of the palletadvancing mechanism, not shown, to the pallet header cleaning station 13to begin another cycle of operation.

In view of the detailed description of the operation of the mechanismgiven in conjunction with the description of the structure and itscontrols, it is not thought necessary to re-state the operation of theapparatus as a whole.

While in the above one practical embodiment of the invention has beendisclosed, it will be understood that the details of structure shown anddescribed are merely by way of illustration, and the invention may takeother forms within the scope of the appended claims.

I claim:

1. Apparatus for removing concrete members from pallets at a palletposition comprising, a rail over the pallet position, a carriage movablealong the rail to a position overlying pallets at the pallet positionand to a position removed therefrom, means to move the carriage alongthe rail, means on the carriage to grip cured concrete members, anelevator at the pallet position on which pallets rest to lift pallets tobring the cured members into engagement with the gripping means on thecarriage and to lower the pallets leaving the cured members held by thecarriage, means carried by the elevator to secure pallets to theelevator to positively pull the pallets from cured members held by thecarriage, and means for inverting cured members including a pair ofmember-receiving cradles, a first cradle located adjacent the positionof the carriage removed from the pallet position to receive curedmembers and movable to turn the cured members a quarter turn, and asecond cradle located to receive members from the first cradle after thequarter turn and movable to turn the members an additional quarter turnto complete the inversion.

2. Apparatus for removing concrete members from pallets as claimed inclaim 1 wherein, there are control means to initiate operation of theapparatus and cause sequential operation of the elevator, grippingmeans, carriage and inverting means.

3. Apparatus for removing concrete members from pallets as claimed inclaim 2 wherein, the control means to cause sequential operation of therespective members includes means operated by contact with the concretemember.

References Cited UNITED STATES PATENTS 2,131,474 9/1938 Henderson 25-413,142,106 7/1964 Wise et al 25120 3,181,213 5/1965 Schaible et a1 251202,431,618 11/1947 Rayburn et a1 214-89 2,554,118 5/1951 Moser 214-89FOREIGN PATENTS 1,062,188 12/1953 France.

I. SPENCER OVERHOLSER, Primary Examiner.

ROBERT D. BALDWIN, Assistant Examiner.

